Beverage-making device

ABSTRACT

An improved beverage-making device, particularly useful for brewing coffee, provides a safety thermostat arrangement for quickly detecting excessive temperatures of a hot water container generally near a heating element arranged therein. A running thermostat provides a self-supporting sensing tube means in cooperation with a capillary tube and thermostat which detect the mean temperature of the hot water and are responsive to a narrow range of temperature variations within the hot water container. The improvement further includes a tap-off hot water system which provides hot water separately and independently of the brewing water heated in said container. The system is connected upstream of the cold water inlet valve of the device and directs cold water into a water coil means residing within the hot water container. Outlet pipe means convey heated water from the coil to an outlet faucet projecting exteriorly of the device. An improved spray disk assembly provides a cooperatively lockable spray disk and mounting collar. The spray disk locks with the mounting collar to tightly seal a flexible gasket around said spray disk whereby the spray disk receives hot water siphoned from said hot water container and evenly distributes hot water in a random dripping flow through the disk. Additionally, a bottom drain system is provided for emptying the hot water container which is non-corrodible and thread disengageable from said container. The drain system provides means for tightly sealing around a bottom drain hole of the container and manually operable valve means to facilitate draining the container.

This application is a divisional application of Ser. No. 633,417, filedJuly 23, 1984.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a beverage-making device which constitutes animprovement over the prior art, particularly directed to those deviceswhich automatically brew coffee.

In such devices, a water supply line is in direct communication with aninlet valve for on-demand admittance of cold water to a water-heatingcontainer in which a constant source of hot water for brewing isavailable. The inlet valve is electrically operated to open for a presetbrewing cycle equal to the amount of time required to provide sufficientliquid to fill a receiving decanter, such as a coffee pot.

A running thermostat senses the temperature in the water container andelectrically communicates with a coiled, or looped, heating element sothat the constant desired temperature is maintained.

Water systems for admitting cold water to the container include inlettube means for dispensing the incoming water at the bottom of thecontainer. As the cold water enters, displaced volumes of hot water atthe top of the container are siphoned from the container to a brewingchamber, which is manually pre-filled with a load of fresh groundcoffee. As incoming water reduces the water temperature in thecontainer, the running thermostat senses this lower temperature andactivates the heating element. The heating element remains energizeduntil the thermostat senses that the required water temperature has beenreached. With high capacity electric heating elements, a substantialtemperature increase occurs over a short period of time. Should therunning thermostat fail in the on position, a so-called "run away"condition will result whereby the heater will stay energized.Thereafter, the heating element will quickly evaporate the water andreach a dangerously high temperature. In order to prevent overheating,conventional systems include high limit thermostats. A high limitthermostat serves to de-activate the heating element when excessivetemperatures are sensed. This safety feature is particularly useful whensomeone has inadvertently failed to fill the water container prior toinitiating a brewing cycle. Without this feature the running thermostatwould blindly sense the ambient air temperature inside the emptycontainer. In response, the heating element would continue to operateuntil reaching a dangerous "red-hot" condition.

Customarily, the hot water container is provided with a hermeticallysealed cover which supportively accomodates the aforesaid siphon,running and high limit thermostats, and inlet tube means, as well as theterminals for the heating element. A drawback to this typicalarrangement is that only the temperature at the cover is sensed by thehigh limit thermostat. As a result, an excessively high temperature atlower portions of the container, localized near the heating element, cansometimes occur while the cover remains relatively cool. The remotedisposition of a high limit thermostat at the container cover isinherently inefficient for detecting these temperature fluctuations atthe bottom half of the container. A thermostat system which canimmediately detect this dangerous condition, and promptly de-activatethe heating element, would be a significant achievement.

Running thermostats are typically connected to an enlarged sensing bulbby means of a thin capillary tube. The bulb end is usually positioned atthe lower half of the container. The capillary tube must thereforeextend downwardly into the container to reach the bulb end. A long guidesleeve is used to hold the bulb in place. The guide sleeve is attachedto the cover and extends downwardly into the container to surround andprotect the capillary tube and the full length of the enlarged bulb end.Usually, guide sleeves are secured to the bottom of the heating coil sothat the bulbs are fixed in the proper orientation. Deficiencies in thisconventional arrangement have been encountered. Firstly, the enlargedbulb end is limited to only sensing temperatures in the vicinity of thebottom half or third of the container. Temperatures at the upperportions are not detected, and may in fact be sufficiently high to brewcoffee without further activation of the heating coil. It would beconsiderably more advantageous to detect the mean temperature of theentire water volume. Secondly, conventional enlarged bulb thermostatshave a temperature-sensing spread of about 6°-8° F. Thereby, the heatingelement is not quickly activated when the water becomes too cool and,once activated, will unnecessarily remain on for a period of time afterthe water has reached the desired temperature. A thermostat arrangementthat reacts to smaller temperature changes would be economicallybeneficial, since the heater would be activated soon after the waterfalls below the usual brewing temperature of 205° F. and thende-activated very shortly after this is attained.

The guide sleeve arrangements in the prior art have hindered maintenanceprocedures. In order to remove the thermostat and bulb for repair, thecover has had to be removed in order to disconnect the guide sleeve fromthe heating element. It would be a great aid to repair personnel toeliminate the need for a guide sleeve and provide a running thermostat,capillary tube and sensing tube that are completely disengageable fromthe device without requiring other components, such as the cover, to bedisconnected or disturbed. A self-supporting sensing means would greatlyadvance the solution to this problem. Savings in maintenance time andrepair costs would be made.

Automatic beverage-making devices have also included means fordispensing hot water for making tea, instant soup and the like. In thepast these systems simply drained hot water directly from the watercontainer. By extracting a volume of hot water from the container, thebrewing capability of the device is diminished. Should a contemporaneousbrewing cycle be desired, the container must first be re-filled withcolder inlet water and then heated to elevate the temperature of thewater to the necessary brewing level. The re-filling step has usuallybeen initiated by the provision of a float switch arranged in the upperportion of the container which detects the drop in the water level. Theinlet valve is electrically controlled by the switch which signals it toopen until the float is satisfied. Due to lime build-up the switches canclose and become inoperable. A hot water system that eliminates the needfor a float switch would be a significant advance in the art. It wouldalso be a valuable improvement to provide a hot water system which doesnot borrow from the water in the container but still makes hot waterinstantaneously available for these other purposes.

In order to distribute the siphoned hot water over the coffee grounds,typical beverage-making devices utilize resiliently biased spray meansover which the siphoned water is directed. The spray means is usually aflat, perforate disk. Other devices have used a showerhead typearrangement wherein a siphon tube nozzle fluidly communicates with aspray means that is concave rather than disk-shaped. Spray means, ineither form, provide for sprinkling hot water over the coffee grounds,which are disposed in the brewing basket, or chamber, therebelow. Foreffective brewing to take place, a "lazy" drip from the spray means ispreferred for a uniform distribution of hot water over the groundcoffee. A common problem, particularly with flat spray disks, has beenthat the siphoned water is too forcefully emitted in streams through aseries of disk orifices which create an equal number of holes bored intothe mound of coffee grounds. Quite oppositely, the desired dripphenomenon is an even flow over the grounds. It would therefore be ofgreat value to provide a moderately paced gravity drip system whicheliminates individual spray streams through the disk orifices onto theground coffee. Spray disks also require cleaning due to the accumulationof lime deposits and other sediments found in water lines. As a result,the disks need to be removed for cleaning. The usual resilientconnections between spray disks and associated mounting collars renderthe disks removable, but are inadequate for achieving a tight engagementtherebetween. A tight seal between the periphery of the spray disk andmounting collar is highly desirable so that the siphoned hot water willnot leak around the edges of the disk, but will be emitted only throughthe orifices.

Accordingly, a more effective interconnection between a spray disk andmounting collar would be a significant improvement over the foregoingdevices. A positively locking connection would void the disadvantages ofthe resilient connections found in the prior art. It would also bebeneficial to provide a tight sealed engagement that also snugly lodgesa flexible gasket between the outer edge of the disk and the collar.Thereby, edge leakage would be prevented and a random drip patternattained for the preferred even distribution of hot water over thecoffee grounds.

For standard size automatic beverage-making devices, the hot watercontainer normally holds at least three times the volume of aconventional coffee pot and usually takes the form of cylinder having agreater height than width. Cleaning these relatively large containers isnecessary for taste and sanitary reasons. In order to removesedimentation, such as lime deposits, the prevailing technique involvesoperating the beverage-making device for several cycles with a de-limingsolution pumped through the container. Often, sediments at the containerbottom are not dissolved and must be manually removed. In a morerudimentary cleaning method, the container is simply tipped over toempty the water. The latter is clearly an awkward and undesirabletechnique. A bottom drain, which allows the container to be fullyemptied, would be preferable. Prior art devices have failed to provide aseparate bottom draining system, probably due to the problemsencountered with attaching drain tubes. The customary manner of affixingdrains to metal containers is by welding. A disadvantage to suchfittings is that the welds corrode and result in leakage. Welding alsocreates a fixed drain connection which impedes removing the containerfor repair and otherwise generally limits access to other componentsinside the device. It would accordingly be of significant value toprovide a non-welded bottom drain system which avoids corrosion andleakage problems. In addition, it would be advantageous for the drainsystem to be disengageable to permit easy access to the interior of thedevice for the repair, or replacement, of mechanical and electricalcomponents.

The present invention offers an improvement for beverage-making devicesof the type described, which satisfies the needs set forth above. Theinvention may be briefly summarized as comprising, in part, a safetythermostat arranged with the container generally near the heater, whichfacilitates the prompt detection of excessive temperatures long beforethe cover becomes overheated. Thereby, a temperature increase can beimmediately sensed in order to de-activate the heating element prior toreaching a dangerous condition.

An improved running thermostat system is provided, which senses the meantemperature of the entire volume of water and has a more precisetemperature-sensing spread than found with previous devices. Thethermostat communicates with the water by means of a self-supportingelongate sensing tube that extends for substantially the full height ofthe container and is connected to the thermostat by means of a capillarytube disposed outwardly of the cover. The unique thermostat and sensingtube arrangement is independently removable from the beverage-makingdevice without disturbing the container cover or any other components.

The improvement further includes a tap-off hot water system whichcommunicates with the incoming water supply upstream of the inletcontrol valve. The tapped-off water is directed into a water coil systemarranged inside the container whereby the surrounding brewing waterserves to heat the tapped-off water. When needed, the hot water isdirected to flow through the coil to a hot water faucet located at theexterior of the device. The volume of hot water available for brewingcoffee is therefore not reduced.

Also, an improved spray disk assembly forms part of the invention. Theassembly eliminates resilient attachment and instead securely, butremovably, locks a spray disk to a mounting collar above the brewingchamber. The disk is easily removed with a simple twisting motionwithout the need for tools. The improved spray disk assembly includes asealing gasket which is tightly held against the mounting collar so thatleakage around the periphery of the disk is eliminated. A series oforifices extend through the disk but a direct spray through each isavoided, and a random "slow-drip" for effective brewing is obtained.

A unique container draining system is additionally provided whichassociates with an aperture at the bottom of the hot water container.The system includes a flanged drain fitting partly arranged interiorlyof the container and partly extending through the aperture to bethread-engaged with an elbow and coupling assembly in a tightly sealedconnection. A conventional valve is connected to the coupling means andis manually operable to facilitate emptying the water container. Thesystem eliminates the problems with welding and affords quickdisengagement from the container to allow easy access to the interior ofthe device.

BRIEF DESCRIPTION OF THE DRAWINGS

The improved beverage-making device is described in conjunction with thefollowing figures in which like reference numerals are used throughoutto identify the same components, wherein:

FIG. 1 is a perspective view of a beverage-making device having theimprovements of the invention housed therein;

FIG. 2 is a schematic view of the entire water flow system for thebeverage-making device of FIG. 1, diagrammatically showing the tap-offhot water system, spray disk assembly and bottom drain system of theinvention;

FIG. 3 is a composite vertical cut-away section and elevational view ofportions of the improved beverage-making device of FIG. 1 showing thehot water container and container cover cut-away to expose, inelevation, the safety thermostat arrangement to one side of thecontainer, the bottom drain system at the bottom of the container, theelectric heating coil having a pair of terminals mounted at the cover,the water coil of the hot water system having inlet and outlet tubesmounted by means of compression fittings at the cover, and the sensingtube for the running thermostat system broken-away just below the cover;other components of the beverage-making device, including the lockingmeans for mounting the sensing tube to the cover, the runningthermostat, and a bracket for altermately mounting a safety thermostaton the cover, are deleted from FIG. 3 for purposes of clarity andexplanation, and are shown in detail in the other Figures.

FIG. 4 is a plan view of the hot water container cover assembly,including the improved running thermostat system associated therewithand the inlet and outlet openings for the water coil shown in FIG. 3;

FIG. 5 is a front elevational view of the improved safety thermostatarrangement as shown in FIG. 3;

FIG. 6 is a sectional view taken along lines 6--6 of FIG. 4 showing thelocking assembly for mounting the sensing tube of the running thermostatsystem to the container cover and a conventional bracket used formounting a safety thermostat at the cover;

FIG. 7 is a perspective view of the mounting bracket for the runningthermostat as shown in FIG. 4;

FIG. 8 is a sectional view taken along lines 8--8 of FIG. 4 showing theoutlet cap and baffle used for controlling the discharge of brewingwater siphoned from the container into a siphon tube;

FIG. 9 is a sectional view of a check valve provided for the hot watersystem as shown in FIG. 2;

FIG. 10 is another schematic view of the entire water flow system of thebeverage-making device, diagrammatically showing an alternativeembodiment for the tap-off hot water system;

FIG. 11 is a sectional view of an alternate combination check and reliefvalve provided for use in the hot water system shown in FIG. 10;

FIG. 12 is an exploded perspective view of the improved spray diskassembly as shown in FIG. 2;

FIG. 13 is an exploded perspective view of a portion of the bottom drainsystem as shown in FIG. 3;

FIG. 14 is a side view of an alternate looped heating element usable inconjunction with the invention; and,

FIG. 15 is a front view of the heating element as shown in FIG. 14.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Introduction

FIG. 1 is a perspective view of the exterior of a coffee-making device10 which has a generally well-known design and includes an upper housing11 and lower housing 12. A brewing chamber 13 is removably held by aconventional slide track means 14 in position for receiving hot watersiphoned from a heated tank disposed inside lower housing 12. Adecanter, or coffee pot 15, is stationed on a warmer 16 and collectsincoming brewed coffee from the chamber. The warmer is activated in theusual way by a switch 17. To keep previously brewed portions of coffeewarm, the upper housing 11 includes two warmers 18 and 19. A decanter 15is filled with coffee and is shown stationed at warmer 18. The coffeemaker 10 may also employ an auxiliary warmer unit 16A of conventionaldesign, shown in phantom lines in FIG. 1.

The coffee maker 10 is operated by means of a control panel 20, whichincludes a main switch 21, a brewing cycle switch 22 and a ready light23. The switch 21 activates the electrical system of the coffee makerwhereby a heating element and thermostat arrangement cause a storedvolume of water to be heated to a desired brewing temperature, as willbe hereinafter described. A ready light 23 is illuminated when thesystem is ready to provide hot water for brewing coffee. At that point,a brewing cycle may be initiated by depressing the switch 22, whereuponthe hot water is siphoned onto coffee grounds contained within thechamber 13. Warmers 18 and 19 are operated by the switches 24 and 25located near the top of the panel 20.

The control panel 20 further includes a hot water faucet 26 extendingoutwardly therefrom, which provides means for dispensing water from thetap-off water system of the invention, as will be described below.

FIG. 2 is a schematic drawing of the internal components of the coffeemaker 10. The upper housing 11 and lower housing 12 are shown in dashedlines. It will be understood that the electrical circuitry for thedevice 10 is provided in a conventional manner, such as found in thewiring system for Model Nos. 8714 and 8715 made by BloomfieldIndustries, Inc., Chicago, Ill. The relationships of the variouscomponents in the wiring scheme, including the improved safetythermostat arrangement and the running thermostat system of theinvention, are intended to be connected in the circuit in this knownmanner, and the circuitry therefore forms no part of the invention.

With reference to FIGS. 2-4, it will be seen that the coffee-makingdevice 10 includes a hot water container, or tank, 27 which is initiallyfilled with a predetermined volume of water. In the illustrativeembodiment, the tank 27 holds approximately one gallon when filled tothe intended maximum level of about one-half inch below the top of thecontainer. When the switch 21 is on, the temperature of the water insidethe tank 27 is monitored by an improved running thermostat system 28.The required brewing temperature is in the range of from about 200° F.to about 205° F. To facilitate heating the water, a sheathed electricalheating coil 29 is arranged within the tank and is in electricalcommunication with the running thermostat system 28. When the runningthermostat system 28 detects that the water temperature has fallen belowthe desired range, the system closes a circuit and activates the heatingcoil 29 until such time that proper brewing temperature is achievedwithin the container 27. The ready light 23 is electrically controlledby the running thermostat system and is not illuminated until theheating element is de-activated.

As best viewed in FIGS. 3 and 4, a cover 30 closes the open top of thetank 27 and is hermetically sealed thereto by means of a gasket 31disposed between the upper rim of the tank and the peripheral lip of thecover in a known manner. The hot water is thereby safely sealed withinthe tank.

When freshly brewed coffee is desired, the brewing basket, or chamber 13is lined with filter paper and then manually loaded with a predeterminedamount of ground coffee. The coffee pot 15, as shown in FIG. 1, may thenbe placed onto the warmer 16 in position to receive brewed coffee fromthe chamber 13. Brewing cycle button 22 is then pushed to initiate thebrewing sequence.

The water flow system for providing brewing water to the chamber 13 isbest understood with reference to FIG. 2, wherein a water inlet pipe 32is arranged at the bottom portion of the housing 12 and is connected toa water supply line (not shown). The inlet pipe 32 is in fluidcommunication with a solenoid valve 33 which is operated by aconventional timer means that begins its sequence when the button 22 isactivated. The timer is calibrated to open the valve 33 for the periodof time required to admit a volume of water sufficient to fill thecoffee pot 15. The valve 33 includes a cleanout 34 to enable it to bebackflushed when lime deposits accumulate at the valve. The flow ratefrom the valve 33 is controlled by an internal flow control valve 35,which in the exemplary embodiment permits 0.75 gallons per minute topass into an inlet pipe 36. The inlet pipe 36 directs the cold waterupwardly into a basin 37 disposed within upper housing 11. The basin 37is formed to have a drain sump 38 for draining incoming water into atube 39. Tube 39 directs the water through an aperture 39' of cover 30and terminates thereat to open into a funnel 40. Funnel 40 is affixed tothe bottom of the cover around aperture 39'. An inlet tube 41 isconnected to the funnel 40 and extends downwardly into the container 27to discharge the cold water near the bottom of the container. Theentering cold water displaces an equal volume of hot water near the topof the container 27 which flows into a siphon tube 42.

With reference to FIGS. 4 and 8, it will be noted that a raised annularshoulder 90 projects upwardly from the cover 30 and has a centralaperture 42' into which the siphon tube 42 is attached to be in fluidcommunication with the hot water. An outlet cap 91 and a baffle 92 arewelded at the undersurface of the shoulder 90 in a typical constructionwhereby the rising, displaced hot water is controlled in its passageupwardly through the aperture 42' into the siphon tube. The siphon tube42 slopes downwardly from the top of the container and discharges thehot water into a spray disk assembly 43, which distributes the waterover the coffee grounds in brewing chamber 13.

Following the timed sequence, the valve 33 is closed, and the heatedwater within the brewing chamber 13 bathes the coffee grounds therein,whereby brewed coffee seeps from the chamber, by gravity, into thedecanter 15. It will be understood that the calibration of the timermeans will preferably be made so that the portions of water absorbed bythe grounds and lost in the form of steam are taken into account inorder that the decanter is filled to the necessary level.

In the event that pressure is built up within the container 27, a venttube 44 is affixed to the cover 30 at the aperture 44' to communicateinteriorly of the container 27. The vent tube extends upwardly from thecover 30 to enter the basin 37 for discharge therein. Accordingly,excess water pressure will be relieved into the basin and be safelydrained back into the container via the drain sump 38.

Since the cold inlet water decreases the tank water temperature, therunning thermostat system 28 will activate the electrical heatingelement 29, in the manner mentioned above. Following a brewing cycle,rapid heating sometimes occurs with certain high capacity heatingelements. If the running thermostat is faulty and sticks in the onposition, a back-up safety provision is needed to de-energize the heaterbefore the water completely boils away and the element overheats. InFIG. 4, a typical arrangement for a safety thermostat 45 is shown inphantom lines and provides a means for detecting an overheating of thecover 30. A standard bracket 46, shown in solid lines, offers themounting means for the safety thermostat 45. In coffee-making devices ofthe type described, the running thermostat and the safety thermostat areconnected in series with the heating element whereby the safetythermostat will override the running thermostat to de-activate theheating element when the cover reaches these overheated temperatures.Generally safety thermostats are manufactured to have an opentemperature of about 226° F. This conventional arrangement has beensatisfactory for heating elements of 1800 watts or less, such as thelooped elements 118 and 118' shown in FIGS. 14 and 15, and therefore maybe practiced with the other features of the invention herein describedfor these lower capacity elements. Therefore, the cover 30 is preferablyprovided with a bracket 46 in the event that the coffee maker 10 isprovided with the lower capacity heating elements. However, thearrangement of the thermostat 45 has been found to be inefficient forthe higher capacity elements which can quickly overheat the lowerportions of the container 27 long before the cover 30 becomes equallyhot.

Improved Safety Thermostat Arrangement

With reference to FIGS. 3 and 5, an improved safety thermostatarrangement is shown for use with the high capacity heating elements andreplaces the existing techniques, such as the thermostat 45 of FIG. 4.In the preferred embodiment, the heating coil 29 is a 230 volt, 4800watt, 11 loop coil. Other high capacity heating elements, similar to theheating element 29, may alternatively be provided, such as a 120 volt,2000 watt coil having 5 loops, or a 230 volt, 3500 watt coil having 8loops.

The top loop of the coils is connected to a conventional terminalassembly T by a vertical section of the heating element. The bottom loopof the coil is connected to a conventional terminal assembly T' by avertical section of the element. Both of the terminal assemblies T andT' provide water tight connections with cover 30 at terminal openings29A and 29B, as best viewed in FIGS. 3 and 4.

It will be observed that the loops of the coil 29 extend annularly nearthe side of the container 27. At these locations rapid increase intemperature can occur. In solution of the problems with prior artsystems, there is provided a manually resettable thermostat 47preferably mounted adjacent the container 27 at or below the mid-pointthereof and generally close to the heating coil. The thermostat 47 hasan exposed bi-metal disk 48 disposed against the side of the container.In the exemplary embodiment, the thermostat 47 is an Essex InternationalControls Division thermostat Model No. 404-58 having an open temperatureof 226° F.±9° F. The thermostat 47 includes terminals 49 and 50 whichare of the spade-type variety, whereby the thermostat 47 is wired to bein series with the running thermostat system 28. The thermostat 47includes a mounting plate 51 affixed to a housing 52 of the bi-metaldisk 48. The plate 51 extends transversely to the terminals 49 and 50and has sidewardly-open notches 53 and 54 at opposite sides thereof. Acooperative bracket 55 is disclosed for the positioning of thethermostat 47 at the desired location along the tank 27. The bracket 55is preferably made of stainless spring steel and has a mounting foot 56and an upwardly extending long arm 57. The foot 56 is mechanicallyfastened by screws S to the bottom of the housing 12 and is made wherebyto form an angle of greater than 90° with arm 57 before attachment inthe coffee maker. The affixation of the foot 56 to housing 12 disposesthe arm 57 at right angles to the foot 56 and thus arm 57 is springbiased toward the container 27 in order to urge the thermostat 47against the container. A mechanical fastening of the thermostat 47 tothe bracket 55 is envisioned wherein the upper end of the arm 57 iscut-out to form a seat 58 intermediate a pair of upstanding side ears 59and 60. The ears 59 and 60 include holes which, as would be understoodare spaced to align with the notches 53 and 54 so that screw fastenersS' may secure the mounting plate 51 to the bracket 55.

Preferably, the thermostat 47 is positioned so that the bi-metal disk 48contacts the side of tank 27 just slightly above the upper loop of theheating coil 29 where rising heat from the coil will create the hottestspot. If temperatures exceeding the thermostat capacity are created atthe bi-metal disk 48, as might occur when a defective or stuck runningthermostat fails to switch off and continues to energize the heatingelement until finally all the water evaporates, the thermostat opens thecircuit to de-activate the heater 29. The thermostat 47 is provided witha manual reset button 62, which requires the operator to make thenecessary reset once the heater has been shut down. A manuallyresettable thermostat is preferable for this safety system, butalternatively, a self-resetting thermostat may also be used. Access tothe reset button 62 is provided by a removably-capped peek hole means 61located in positional correspondence with the thermostat 47 along thefront face of the housing 12, as shown in FIG. 1. A small screwdriver,for example, may be used to push the button 62 and reset the thermostatfor subsequent use.

Improved Running Thermostat System

The running thermostat system 28, which heretofore has been generallydiscussed with regard to activating and de-activating the heatingelement 29, will now be described in greater detail with reference madeto FIGS. 3, 4, 6 and 7. System 28 is an improvement over previouslyknown arrangements, particularly because the mean temperature of theentire water volume is sensed. Also, temperature variation is sensedwithin a very narrow range. These are significant advances in thebeverage-making art because the device 10 is thereby renderedconsiderably more efficient by only operating the heating element whennecessary.

The improved running thermostat system 28 includes a thermostat 63located at the cover 30. The thermostat 63 has an adjustable controlshaft 64 that enables the thermostat setting, and thereby the brewingwater temperature, to be varied. Preferably, the thermostat 63 has theoperating capacity of a ROBERTSHAW Controls Company thermostat No.K-944-12, or equivalent. Other suitable devices will be apparent tothose skilled in the art. The thermostat 63 is affixed with a mountingflange 65 having a pair of engageable holes 66 and 67. A cooperativemounting bracket 68, best shown in FIGS. 4 and 7, supports the mountingflange 65, and thereby the thermostat 63, at cover 30. The bracket 68comprises a lower plate 69 integrally formed with a vertical plate 70,which includes a vertical slot 71, a horizontal slot 72, and a central,upwardly open notch 73. The slots 71 and 72 correspond to the spacing ofthe holes 66 and 67 of the mounting flang 65. Screw fasteners 74 and 75are provided to be received through the slots 71 and 72 and thereafterengaged within the holes 66 and 67 whereby to releasably hold thethermostat on the bracket. In this arrangement, the thermostat 63 iseasily removable from the bracket 68 by partially unthreading the screwsand thereafter simply moving the thermostat first upwardly to disengagethe fastener 74 from the slot 71, and thereafter sidewardly to removethe fastener 75 from the slot 72. This removability is a significantadvantage for repair personnel since, unlike previous devices, thesethreaded fasteners need not be removed and therefore cannot becomeaccidentally dropped within the housing of the coffee-making deviceduring repair.

A short capillary tube 76 associates with the thermostat 63 in aconventional manner. However, the capillary tube 76 does not extenddownwardly into the container 27 to meet a bulb end, such as found inthe prior art. Instead, a unique elongate and self-supporting sensingtube 77, best viewed in FIGS. 3 and 6, extends downwardly from thecover. The sensing tube 77 is joined to the capillary tube 76 interiorlyof a fastening assembly 78, shown in the sectional view of FIG. 6. Thesensing tube 77 offers a great advance over the existing thermostatsystems inasmuch as no guide sleeve is needed. Further, the sensing tubeneed not be attached to the heating coil, which is customary with knownguide sleeve systems in order for the bulb to be maintained in theproper vertical orientation at a specified depth within the hot watercontainer.

The sensing tube 77 is hollow and is preferably made of stainless steel.A conventional oil is contained within the tube 77 and is in fluidcommunication with the capillary tube 76 as would be clear. Sensing tube77 extends downwardly within the coils of the element 29 and terminatesgenerally near the bottom thereof in a crimped end 79. The tube 77thereby extends for substantially the full height of the container 27and renders the system 28 capable of detecting the mean temperature ofsubstantially the entire volume of water within the tank. Existingcapillary bulb devices usually have an outer diameter of greater than0.30 inches. Thus, a guide sleeve of greater diameter is required tosurround the bulb end. In preferred form, the sensing tube 77 has anoutside diameter less than 0.30 inches and therefore occupies a smallerspace. It has been found that this thinner construction allows the oiltherein to be quickly sensitive to the temperature changes whereby thetemperature detected at the thermostat 63 is closely reflective of thetemperature fluctuations within the tank. As a result, the sytem 28 iscapable of responding to temperature change in a range of from about 2°to 3° F. spread and at least before a 6° F. change has occurred.Existing systems are less precise and are responsive to spreads of about6° to 8° F., or more.

Reference is now made to the locking means 78 shown in the sectionalview of FIG. 6. It will be seen that the capillary tube 76 is solderedto a tapering upper end of the sensing tube 77 generally denoted byreference numeral 80. A female fitting 81 is weld-connected within andaround an aperture 82 extending through the cover 30. The fitting 81includes a centrally threaded bore 83 which is thread engageable with alock nut 84. The lock nut 84 is hollow whereby to permit the capillarytube to pass therethrough and be joined with the tube 77 at the solderconnection 80. At its lower end, the bore 83 includes an inwardlyextending annular shoulder 85 forming a bearing seat within the fitting81. A collar 86 is soldered around the upper end of the sensing tube 77generally below the solder connection 80 and includes a peripheralshoulder 87. Between the peripheral shoulder 87 and the annular shoulder85, a water tight sealing means is provided by a rubber gasket 88 andmetal washer 89, which are compressed by the lock nut 84 as it threadsdownwardly into engagement with the bore 83. Lock nut 84 also securelyfastens the collar 87 within the fitting 81 and thereby fixes thesensing tube 77 in the orientation illustrated in FIG. 3.

It will be appreciated that the running thermostat system 28 iscompletely disengageable from the cover 30 without the removal ordisturbance of any other components. Specifically, the thermostat 63 canbe disengaged from the bracket 68 as explained, and by untightening thelock nut 84, the sensing tube, with the capillary 76 attached thereto,may be drawn upwardly out of the aperture 82 in a facile manner. Whenthe need to replace the thermostat 63 arises, repair is thereforeexpedited and maintenance costs are reduced. It is contemplated thatreplacement of the thermostat 63 will not be required as often as withexisting systems due to the capability of system 28 to sense the meantemperature of the water within a narrow temperature spread. By quicklyreacting to the water temperature changes, the heater is activatedbefore the temperature drops no more than 6° F. below the usuallydesired brewing temperature of 205° F. Furthermore, the heating elementwill not remain activated as long, since as the temperature is raised,the system 28 will react to de-activate the element at no greater thanabout 6° F. above the brewing temperature. This efficiency is criticalwith high capacity heaters because they tend to deteriorate much morequickly than the lower capacity elements. It will also be clear that thehot water is almost always made available at the proper temperature formaking coffee. The capability of the system 28 to minimize thisactivation time and keep the water at the desired temperature aresignificant benefits of the invention.

Tap-Off Hot Water System

The invention further provides a tap-off hot water system which does notborrow from the water content within the container 27 and requires nofloat switch means. With reference to FIGS. 2, 3 and 9, it will beobserved that the tap-off hot water system is generally denoted byreference numeral 93. A significant feature of the system 93 is that ittaps cold water from the inlet pipe 32 by means of a T-fitting 94located upstream of the inlet valve 33. A check valve 95 is connected tothe T-fitting 94 by a suitable connecting pipe means whereby a minimumwater pressure is required before water is introduced into the system.The check valve 95 has a conventional construction, as shown by thesectional view thereof in FIG. 9, wherein a spring biased valve 96controls the passage of water from an inlet chamber 97 into an outletchamber 98. In the preferred embodiment, the check valve 95 requires 2p.s.i. of pressure to open.

Water conveyed through the check valve passes straight through aT-fitting 99 into a tube 100 which directs the cold water into acompression fitting 101 sealingly arranged within an aperture 101' atthe cover 30.

The important characterizing feature of the tap-off hot water system isthe arrangement of a water coil 102 within the container 27. The watercoil 102, in preferred form, is a hollow stainless steel tubing havingabout at least an 8 ounce capacity. The coil 102 is concentricallyarranged above heating element 29 and spaced below the cover 30 as shownin FIG. 3. Coil 102 includes an upright cold water receiving tube 103communicating with the lowest loop of the coil and a shorter upright hotwater outlet tube 104 communicating with the topmost loop of the coil.The tube 103 is connected to the compression fitting 101 below the cover30 to be in fluid communication with the tube 100. Cold water enteringfrom the tube 100 thereby circulates through the coil 102 and is quicklyheated due to the constantly maintained temperature of the waterresulting from the on and off activation of the heating element 29, asdescribed above.

It will be observed that in the preferred embodiment the water coil 102includes 14 loops arranged in a helical formation wherein adjacent loopsare in contact. No need for additional heating of the coil is requiredsince it is placed generally at the upper half of the container 27 andis continuously surrounded by hotter rising water circulating past theindividual loops. A second compression fitting 105 is sealingly arrangedwithin an aperture 105' of the cover 30 and is connected to the outlettube 104 below the cover 30 and to a hot water discharge tube 106 abovethe cover. The discharge tube 106 conveys hot water outwardly of thecontainer 27 to pass through a speed valve 107 associated therealong.The speed valve 107 is manually operable to permit varying the waterpressure therethrough, such as when there are changes in the watersupply pressure entering the inlet pipe 32. The outlet tube 106 extendsgenerally horizontally toward the control panel 20 and is connectedthereat with a lever-action faucet 26, as best viewed in FIGS. 1 and 2.The faucet 26 is preferably a conventional 100 p.s.i. to 150 p.s.i.faucet, well known to those skilled in this art.

When hot water is needed for making tea, instant soup, hot cocoa, etc.,the faucet 26 is manually opened and cold water flows inwardly from theinlet 32 through the inlet tube 100 into the coil 102 to force hot waterin the coil to be pressured outwardly thereof into the tube 106 anddispensed via the faucet 26. Due to the continuous heat transferred tothe coil from the hot water in the container and the unique helical coilarrangement, by the time the cold water entering from the inlet tube 100reaches the outlet tube 104, it is as substantially as hot as thebrewing water within the container 27. Thus, a constant source of hotwater is readily available without the need to borrow from the contentsof container 27. It will be appreciated that there is no need to provideany float limit switches which are otherwise required in conventionalhot water systems that simply drain the water tank to obtain hot water.

Since the water heated within the coil 102 will naturally expand andincrease the pressure in the system 93, the faucet 26 may experiencepressures in excess of its capacity and leak. Relief for this pressureis provided by a pressure chamber 108, which is connected to thetransverse stem of the T-fitting 99 by a standard elbow 109, shown inFIG. 2. Any excess water pressure caused by expansion in the coil 102will therefore be relieved through the tube 100 into the chamber 108 andprevent leakage at the faucet 26, or for that matter, at any othercomponents within system 93.

The placement of the pressure chamber 108 is envisioned to be verticallywithin the lower housing 12 of the coffee maker 10 generally at a cornerthereof and spaced from the container 27. In conventional housingdesigns, the standard box-shaped lower housing affords room at either ofits rearward corners which provide sufficient space for stationing thepressure chamber 108.

An alternate embodiment of a pressure relief means for the system 93 isdisclosed in FIG. 10. The same reference numerals are used to denote thesystem 93 in both FIGS. 2 and 10, with the exception that in FIG. 10 theinlet tube comprises two sections, denoted 100A and 100B, and it will beobserved that these A and B sections are created by re-positioning theT-fitting 99. In this alternative, the pressure chamber 108 is deletedand the T-fitting 99 is re-located upwardly along the inlet tube section100A generally adjacent the cover 30. The stem of the T-fitting isoriented in the opposite direction with respect to that shown in FIG. 2.In this embodiment, the stem of the T-fitting is engaged with the inlettube section 100B, which directs the water flow into the coil 102 asexplained above. The other arm of the T-fitting is connected to astandard pressure relief valve 110. The relief valve 110 preferably hasan open pressure capacity of about 100 p.s.i. to 110 p.s.i., so that itwill open at a pressure level below the pressure capacity of the faucet26, as would be clear.

Downstream of the pressure relief valve 110 a suitable elbow 111connects the valve to an everflow tube 112. The overflow tube 112extends to pass through the wall of the basin 37 for discharge ofoverflow water into the basin. Thus, the system 93 will be relieved ofexcessive pressure by discharging it into the container 27 via the drainsump 38 in a similar manner to the action of the vent tube 44.

FIG. 11 shows a twin valve assembly 113 alternatively usable in theembodiment illustrated in FIG. 10. The twin valve assembly 113 includes,in a single housing, a check valve 114, a pressure relief valve 115, aT-fitting 116 and an elbow 117, which respectively replace the checkvalve 95, the pressure relief valve 110, the T-fitting 99 and the elbow111, shown in FIG. 10. The check valve 114 and the pressure relief valve115 are provided to open at the same respective levels of water pressureas described for the check valve 95 and the pressure relief valve 110.Thus, incoming water from the inlet tube section 100A is directed intothe section 100B through the T-fitting 116. When excess pressure isexperienced by the system, the relief valve 115 opens and directs waterthrough the elbow 117 into the overflow tube 112. It is envisioned thatthe twin valve assembly 113 would be arranged within the system 93 insubstantially the same location as the T-fitting 99 shown in FIG. 10.

In preferred form, the inlet and outlet pipe means for the system 93comprise standard one-quarter inch copper tubing but, of course, theymay have a larger or smaller size as needed.

While the hot water system 93 has been described in conjunction with abeverage-making device 10 having a high capacity heating coil 29, itshould be apparent that the unique design for the water coil 102 permitsthe system to be equally suited for use in devices having a variety ofheater arrangements. For example, the system 93 may be provided incombination with lower capacity heaters, such as the elements 118 and118' (phantom lines) shown in FIGS. 14 and 15. The elements 118 and 118'each have a pair of terminals t and t' which are capable of beingsecured to a tank cover in substantially the same manner as theterminals T and T' of the heating coil 29. The element 118 is a 100-120volt single loop heater having a 1300-1500 watt capacity, particularlyuseful for standard electrical circuits in the United States, Canada andJapan. The element 118' is a 220-240 volt single loop heater having an1800 watt capacity for use in the standard electrical circuit systemsfound in Europe. Each heating element is formed to have a narrowelongate J-shape (FIG. 14) which is adapted to be arranged within a hotwater tank generally at the central long axis thereof. It will beunderstood that the coil 102 is capable of being disposed within thetank to circumscribe either heater element 118 or 118' whereby thesystem 93 operates in the same way as explained above.

Clearly, the coil 102 may be provided to have a different diameter andnumber of looped coils so to be appropriately sized for variouscylindrical tank dimensions. A wide variety of loop shapes are alsointended to fall within the scope of the invention. It will be apparentthat the water coil is not limited to a helical configuration and may besuitably shaped for use in containers that are polygonal incross-section.

Improved Spray Disk Assembly

With reference to FIGS. 2 and 12, the improved spray disk assembly ofthe invention is shown and is generally denoted by reference numeral 43,previously mentioned above. FIG. 12 is an exploded perspective view ofthe assembly 43, which comprises a mounting collar 119 associating witha flexible gasket 120 and a spray disk 121. The mounting collar 119 isaffixed at an undersurface 122 of the upper housing 11 around an opening123 therethrough, which communicates with the siphon tube 42. The collar119 comprises a circular top plate 124 having a central opening 123arranged at the opening 123. In the exemplary V embodiment, the topplate 124 is welded to the undersurface 122 and has a dependingperipheral side wall 125 formed therewith. The side wall 125 includes apair of diametrically opposed bayonet slots 126 which downwardly open at127 and upwardly terminate in horizontal portions 128. The gasket 120 isprovided with an outside diameter substantially equal to the insidediameter of side wall 125 and has a height slightly less than the heightof the side wall and sufficient to extend from the top plate 124downwardly to meet the horizontal portions 128.

In the past, a siphon tube simply discharged onto a spray disk which wasresiliently held by a mounting collar. The improved assembly 43 providesrigid locking and tight sealing between the mounting collar 119 and thedisk 121 whereby leakage about the periphery of the disk 121 is avoided.The disk 121 is best described as a generally circular plate having adiameter sized to snugly fit within the side wall 125 and includes apair of oppositely extending radial tongues 128. The tongues 128 includeflat sections 129 adjacent the disk edge and terminate outwardly inU-shaped portions 130. By grasping the U-shaped portions 130, the flatsections 129 are engageable at the bayonet slots 126 by moving the disk121 upwardly to dispose the sections 129 within the openings 127.Thereafter, the disk is rotated in a clockwise direction to securelylodge the sections 129 within the horizontal portions 128. Thereby, thegasket 120 is sealed against the top 124 and the disk 121 whereby toprevent leakage between the disk and the side wall 125.

The disk 121 is provided with a series of orifices 131 which arearranged to form a central imperforate portion 132. Water, dischargingfrom the container 27 through the siphon tube 42, drips onto thisimperforate portion 131 and flows outwardly therefrom to randomly dripthrough the orifices 131. As previously described, the flow controlvalve 35 preferably limits the inlet rate of water flow to the tank 27to about 0.75 gallons per minute. As a result, water is siphoned fromthe tank 27 in a moderate pace whereby the water pressure emitted fromthe siphon tube 45 will be measured to be less than one inch of mercury.

The tight seal created by the locking engagement of the tongues 128within the bayonet slots 126 assures that the water is directed throughthe orifices and is prevented from leaking around the edges of disk 121.

When cleaning is required due to the accumulation of lime, or othersediments, the operator can easily disconnect the disk by grasping theU-shaped portions 130 and then twisting the disk 121 counterclockwise todisengage the sections 129 from the slots 128. This locking feature ofthe assembly 43 will thereby be appreciated as providing a rigid, butremovable, securement between the disk 121 and the mounting collar 120,while completely eliminating any reliance upon resilient connectionswhich have proven unsuccessful heretofore.

Drain System

A unique drain system 133 is provided for emptying the hot watercontainer of the beverage-making device 10 and is best viewed withreference to FIGS. 3 and 13. The drain system 133 associates with acentral drain hole 134 at the bottom 135 of the container 27. The system133 includes a drain fitting 136 which has an open bore 137 forreceiving drainage therethrough and an upper annular flanged seat 138residing interiorly of the container 27. A threaded stem 139 isintegrally formed with the seat 138 and extends downwardly through thedrain hole 134. The bottom of the seat 138 is beveled at 140 and thecontainer bottom 135 includes a cooperatively depressed annular bevel140' around the drain hole 134 whereby the seat 138 can be flushly andtightly sealed at the bottom 135.

A coupling means comprising a female elbow 141 is provided forengagement with the external threading of the fitting 136. In order forthe elbow 141 to threadably engage the fitting 136, the drain hole 134and the stem 139 have flat sides 142 and 143, respectively. Thereby, thebottom 135 is cooperative to act like a wrench and prevent the fitting136 from rotating in order to facilitate the engagement, ordisengagement, of the elbow 141.

The elobw 141 includes an upper annular seat 144 for the accommodationof an O-ring 145 therein. Upon thread engaging the elbow 141 to thedrain fitting 136, the O-ring 145 is compressed to seal against theundersurface of the annual bevel 140' to prevent leakage therearound. Astandard male coupling 146 engages the outlet side of the elbow 141, andat its opposite end engages with a reducer coupling 147. A thirdcoupling 148 engages the other side of the reducer coupling 147. Lastly,a manually operable drain cock 149 engages the outlet end of thecoupling 148. The coupling assembly 146-148 is of a sufficient lengthwhereby to dispose a drain cock 149 adjacent the housing 12. An accesscut-out (not shown) is provided through the housing so that the draincock can be easily reached when needed. In FIG. 3, a hose 150, shown inphantom, is connected to the drain cock in order to drain the water fromthe tank 27 into a sink, pail, etc.

In conventional beverage-making devices, a removable rear panel isprovided so that access to the internal components can be obtained formaintenance and repair. By the provision of the drain system 133, itwill be clearly understood that the elbow 141, the coupling assembly146-148 and the drain cock 149 are fully removable as a unit by simplydisconnecting the elbow 141 from the drain fitting 136. Thus, not onlycan the system 133 be repaired, if necessary, but other surroundingcomponents within the device 10 may be easily reached by simplyremoving, and later easily replacing, the system.

The system 133 required no welded connection with the tank 27, andtherefore the corrosion problems inherent in previously known weldedfittings is totally eliminated.

ACHIEVEMENTS

An improved beverage-making device has been disclosed which safely andefficiently controls the heating element for the hot water container bythe provisions of an improved safety thermostat arrangement and animproved running thermostat system. Additionally, the invention includesa tap-off hot water system which dispenses hot water without borrowingfrom the hot water container. Further, the invention achieves the goalof providing an improved spray disk assembly that offers a tightlysealing locking means for the disk whereby the brewing water is evenlyand moderately distributed over all the coffee grounds contained in thebrewing chamber. Moreover, the invention provides for the completedraining of the hot water tank by means of a unique bottom drain systemremovably engaged at the bottom of the container in a tightly sealingnon-corrosive connection.

While the foregoing description of the invention has been directedtoward a preferred embodiment therefor, it will be apparent to othersthat various modifications and alternative embodiments fall within thescope of this disclosure and the claims appended hereto.

What is claimed is:
 1. In a beverage-making device of the type generallydefined by an upper and lower housing, a hot water container arranged inthe lower housing, said hot water container fluidly communicating withoutlet means for discharging heated water therefrom and directing thewater to a perforate spray disk means, said spray disk means associatingwith said upper housing at an aperture therethrough whereby dischargingwater is directed to be dispensed downwardly therefrom, the improvementcomprising a spray disk assembly having mounting collar means arrangedat said upper housing and including aperture means in fluidcommunication with said outlet means, said mounting collar means furtherhaving a continuous downwardly open side wall, said side wall includingat least one engageable slot having a downwardly open portion and ahorizontal slot extending therefrom, a perforate spray disk capable offitting within said continuous side wall, said spray disk having atleast one outwardly extending portion capable of engaging saidengageable slot, and a flexible gasket arranged within said mountingcollar means and capable of forming a seal between said mounting collarmeans and spray disk upon engagement of the extending portions at saidengageable slot, whereby water discharged from said outlet means isconstrained to flow through said perforate disk and wherein leakagebetween the side wall of the mounting collar means and the spray disk isprevented.
 2. The improvement as in claim 1 wherein the flexible gaskethas a height slightly less than the height of the side wall.
 3. Theimprovement as in claim 2 wherein the perforate spray disk includes aplurality of perforations arranged in a pattern to form an imperforateportion of the spray disk directly below said mounting collar aperturemeans.
 4. The improvement as in claim 2 wherein the engageable portionof the spray disk includes a flat section adjacent the disk and aU-shaped portion spaced outwardly from the disk, whereby the U-shapedportion provides holding means for manually engaging said spray disk tosaid mounting collar means.
 5. The improvement as in claim 2 wherein thepressure of the hot water emitted from said outlet means is no greaterthan one inch of mercury.